Common name: Curly Flat-sedge
Cyperus rigidellus (Benth.) J.M.Black APNI*
Description: Slender annual or tufted perennial, occasionally viscid.
Culms triquetrous to terete, often scabrous above, 3–25 cm high, 0.6–1.3 mm diam.
Leaves not septate-nodulose, mostly longer than culms, usually curly at the apex, to 3 mm wide. Inflorescence head-like or simple, with 1–4 branches 1–6 cm long; clusters dense to loose, subdigitate, hemispherical to globose, to 30 mm diam.; involucral bracts leaf-like, 2–4 much exceeding inflorescence. Spikelets flattened, 5–15 per cluster, 4–25 mm long, 2.5–4 mm wide in side view, 6–25-flowered; rachilla narrowly to broadly winged; glume spacing 1.3–2.3 mm; spikelet falling as unit, or rachilla persistent. Glumes acute to obtuse with straight to excurved mucro to 0.4 mm long, with sides 2- or 3-nerved, 1.8–3.7mm long, straw-coloured tinged red-brown or evenly red-brown. Stamens 3. Style 3-fid.
Nut trigonous, narrow-obovoid to very narrow-ellipsoid, nearly as long as glume, 1.3–3.2 mm long, 0.5–0.8 mm diam., pale brown; falling with glume only if spikelet is viscid.
Distribution and occurrence: Grows in ephemerally wet situations, such as floodways and roadside drains; plains west from Garah and Pilliga, and north of Condobolin.
NSW subdivisions: NWP, SWP, NFWP
Other Australian states: Qld Vic. W.A. S.A. N.T.
A variable species that may include several taxa.
Text by K. L. Wilson
Taxon concept: Flora of NSW 4 (1993)
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.